Question about the "sawdust plus glue" technique ...

[Izzy Charo]

I have a joint that didn't quite come together flush, and am considering mixing some sawdust from the project wood with glue to fill it. I am planning using Titebond 3 for the joint. I know lot of people do this to fill gaps, but PVA glue doesn't take finish well...so I'm a bit confused. Thanks for all advice-

[Lee Schierer]

If possible, fill the gap with a thin sliver of wood, it will be less noticeable than sawdust. Before you glue it in, apply your stain to the joint area and sliver if you are coloring the area so the glue won't show.

[Prashun Patel]

The sawdust + glue technique will look like sawdust + glue. You're right. It does not take finish the same way as the wood.

Try a thick plane shaving - even if you have to fold it to get the right thickness. You'll mask best if you can roughly match the grain direction.

[Greg Quenneville]

The sawdust + glue technique was true when people used hot hide glue, which will take a finish. Modern glues which don’t include melted down horses do not.

I an friends with a couple who restored furniture for some famous museums, collectors and government. They do in fact sometimes have to resort to sawdust and hide glue. Or rabbit glue. Good enough for the Henry Ford, or the Guggenheim, good enough for me.

[Jim Becker]

Best practice is always to try and fill gaps with solid wood first because, as you note, "glue and dust" and other fillers pretty much will never look like wood and don't take coloration agents and finish well. Cutting slivers of the same wood from the project so that the grain direction matches can often make the gaps completely disappear even to close inspection if you do it carefully and thoughtfully. I've done this a lot including with hand cut dovetails that were not, um...the best fits...and in that case, putting the slivers in diagonal to the joint to that the endgrain is visible on both sides of the joint totally disappears.

[Stan Calow]

Elmers makes (or did recently) a PVA glue that they said was stainable. I've never tried it so don't know if so. I haven't looked for it lately.

edit - yes they still do: https://www.amazon.com/Elmers-E730-Stainable-Wood-8-Ounce/dp/B000LNVAVO

looks like a mix with wood fibers already in it. If that's what makes it stainable, I suspect its no different than mixing it yourself. Maybe someone here has tried it.

[Jamie Buxton]

Bigger gaps should be filled with wood. But when the gaps are so small that wood just doesn't work, sanding dust plus glue does work. Use sanding dust, not saw dust. I use fifteen-minute epoxy. It doesn't shrink like PVA, and cures harder.

[Bryan Lisowski]

If it’s a small gap, CA glue and sanding works well. Put some CA glue in gap, then sand by hand to get sawdust in the gap on top of CA glue.

[Frank Pratt]

I'm glad the dirty little lie about sawdust & glue being a great filler is finally being addressed in public. At least with PVA glue, you might as well use drywall compound because it matches just about as well. I haven't tried it with hide glue or epoxy though.

[Tim Andrews]

I have also had poor results using glue and sawdust, and I have done multiple tests since so many people claim success. I had slightly better results using white glue instead of yellow glue, but nowhere near consistent enough. CA glue wasn’t any better for me. Light woods like maple seem to react differently than dark woods like walnut. For all of the glue techniques, there often seems to be a darker edge around the perimeter of the filled area, and any spillover often darkens the wood underneath which must be sanded off.

My best results come from mixing different colors of Timbermate wood filler to achieve a reasonably close color match. For my latest project in curly maple, I started with their maple, which was too yellow, so I added about 50% white to reduce the color saturation. That brought the hue closer, but was a bit too light, so I added about 10% walnut and the result was pretty close.

If anyone has good results with any other techniques, I would love to hear them!

[Howard Pollack]

I sometimes use sawdust plus whatever finish I'm going to use. I find that it works much better than sawdust and glue. -Howard

[Thomas McCurnin]

I add a drop or two of woodworking dye roughly matching the finish I will be using. Just a little dab will do ya.

[Izzy Charo]

Great discussion...Thanks!

[andy bessette]

...fill the gap with a thin sliver of wood, it will be less noticeable than sawdust...

This. Sawdust and glue looks like crap. Very unpropfessional.

[Chris Sonego]

On dovetails, the dust and glue looks terrible taking ways the sharp crisp line we strive for. As mentioned above a well executed sliver of wood will maintain that crisp line and usually won’t be detectable. Too many YouTube “influencers” do the dust and glue when they should be showing better joinery or the used of wood slivers.

[mark mcfarlane]

For really small gaps (i.e. ones that barely create a shadow line) I've had luck with retouch crayons such as these: https://homesteadfinishingproducts.com/touch-ups-hide-glue-solvents-misc/

Stain project as required then put on the first layer of clear coat. Add blue tape on both sides of the crack. Heat up the crayon with a lighter or whatever to soften it and rub into the crack. Wipe excess away with a soft cotton cloth leaving just a hair-sized sliver in the crakc. You may need to mix a few colors.

Works best if one side of the crack is parallel to the grain.

Putting the crayon on after the first clearcoat prevents the crayon from seeping into adjacent open pores (which will look horrible). The clear coat followed by tape makes the wipe-clean step super easy.

I'm sure I learned this technique on this forum but can't remember who told me.